In MRI Ruby 2.0, how thorough is GC.start?
Does it try to garbage collect all objects that no longer have a reference to them? Or does it only GC objects if it thinks it's necessary?
I'm trying to track the number of objects of a certain class I have, and it seems to keep on increasing even though I think some of the objects no longer have a reference to them. Using GC.start doesn't fix this. I don't use any C extensions, so that can't be complicating things.
Edit: The problem I was having was the same as in Ruby Symbol#to_proc leaks references in 1.9.2-p180? - objects still existed when I thought they ought to have been garbage collected, and like in that case, the problem was to do with using implicit Symbol -> Proc. However, it would be nice to know if GC.start is expected to garbage collect all objects, or merely collect whatever MRI thinks is necessary to garbage collect.